package third;

public class five_25 {
    public static void main(String[] args) {
        for(int k=10000;k<=100000;k+=10000) {
            double e = 0.0000;
            double item = 0.0000;
            for (int i = 1; i <= k; i++) {
                item = Math.pow(-1,i+1)/(2.00*i-1.00);
                e += item;
            }

            System.out.println(4*e);
        }

    }
}
